Generally, snap-action switches of the butterfly-type are well-known in the prior art. Such a prior art snap switch is illustrated and described in U.S. Pat. No. 3,612,793 issued on Oct. 12, 1971, to John O. Roeser and entitled "Electrical Switch Components And Switches Formed Thereby," which is hereby incorporated by reference. As can be seen from FIGS. 1-14 of the '793 patent, there is shown a two circuit snap switch mechanism 10 which is comprised of a support means 12, movable actuation means 14, combination switchblade and contact means 16, terminal means 18, and sealing means 20. In operation, when the button 72 of the actuation means 14 is depressed the elongated member 74 is caused to move downwardly against the bias of the return springs 76 and 78. The combination switchblade and contact means 16 is initially restrained by means of the lower fixed contact portions 156 so that the lower contact portions 130 of the movable contact members 109a, 109b remain in contact therewith.
This contact engagement continues until the pivot points 106 pass the center line of the tension spring 120. At that time, the movable contact members 109a, 109b will snap overcenter and the upper contact portions 130 thereof will become engaged with the upper fixed contacts 148. This engagement continues until the pressure upon the top of the button 72 is released, thereby causing the return springs 76 and 78 to return the elongated member 74 and the button 72 to their original rest position. As the elongated member 74 returns past the center line of the tension spring 120, the movable contact members 109a, 109b will snap overcenter again in the reverse direction. In this manner, there has been provided a snap-action switch which produces closing and opening of mechanical contacts through means of physical movement thereof for making and breaking a circuit.
Furthermore, there is also heretofore known in the prior art electronic components which are capable of providing selective connecting and disconnecting of circuits by solid-state means without the need of physical movement of mechanical contacts. However, these solid-state type of switches have been formed as separate units within their own casing.
In certain applications such as, for examples in the aerospace industry, there has arisen a need for switches which can provide both a mechanical type of switching and a solid-state type of switching. The mechanical contacts are able to handle higher power applications while the solid-state type switches handle a relatively low level of power but exhibit high reliability. It would be desirable to provide a novel and improved hybrid switch which combines a snap-action switch of the butterfly-type and a solid-state type switch into a single compact housing.